1. Field of the Invention
The invention relates generally to methods of forming an imprint on a resin-molded product, and a resin-molded product.
2. Description of Related Art
A known ink cartridge for use with an inkjet printer is a resin-molded product. Inkjet-printer manufactures provide genuine ink cartridges, but counterfeit or compatible ink cartridges also are commercially distributed. The counterfeit or compatible cartridges may have substantially the same appearances as or similar appearances to the genuine cartridges. Inkjet printers offer enough performance expected by the inkjet-printer manufactures when used with genuine ink cartridges. Nevertheless, inkjet printers may offer lower performance when used with counterfeit or compatible ink cartridges.
Another known ink cartridge may have a mark to indicate that the ink cartridge is genuine. Nevertheless, such a mark may be copied, and the copied mark may be put on a counterfeit or compatible ink cartridge. To prevent the mark from being copied, yet another known ink cartridge may have a hologram sticker or reflector as the mark. Such a known ink cartridge is described in JP-A-2000-1036 and JP-A-2004-174873, for example. By detecting light reflected by the hologram sticker or reflector, it is determined whether the ink cartridge is genuine. It may be relatively difficult to reproduce the hologram sticker or reflector with a color copier or other means.
Nevertheless, the manufacturing cost of the hologram sticker and the reflector is relatively high. Moreover, if the manufacturers of counterfeit or compatible ink cartridges obtain a high skill, they may be able to analyze and copy the hologram sticker or reflector. In such a case, a counterfeit or compatible ink cartridge may be determined as genuine.